Spring-collet mechanism for activating a fire extinguisher

ABSTRACT

A method of actuating an extinguisher system may comprise retaining a broadhead cutter in close proximity to a burst disc surface, receiving an impulse signal, actuating a spring release mechanism in response to receiving the impulse signal, driving a cutter shaft towards the burst disc surface in response to actuation, and piercing the burst disc surface via the broadhead cutter coupled to the cutter shaft.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a divisional of, and claims priority to, and thebenefit of U.S. patent application Ser. No. 14/602,811, filed on Jan.22, 2015, and entitled “SPRING-COLLET MECHANISM FOR ACTIVATING A FIREEXTINGUISHER” which is incorporated by reference herein in its entirety.

FIELD

The present disclosure relates to fire extinguisher systems and theircomponents.

BACKGROUND

Today's modern aircraft use hermetically sealed fire extinguishers thatare opened, or activated, by direct explosive impingement energy. Withreference to Prior Art FIG. 1, the device which provides the explosiveenergy is typically called a cartridge 120, or squib. The impingementenergy is focused on a dome-shaped hermetic burst disc 110 such that theburst disc will rupture as a result of the impingement. The burst discmaterial used is typically fabricated from corrosion resistant steel.

Typically, the cartridge 120 is retained in a discharge head 130 in sucha manner that it directly faces the burst disc 110 assembly. Thedischarge head 130 is attached to the outlet of the fire extinguisherand is typically used to direct the flow of extinguishing agent to anaircraft interface, such as plumbing or tubing, which directs the agentto the desired location. A filter screen 150 is located within thedischarge head to catch any large burst disc fragments created as aresult of the explosive impingement energy.

SUMMARY

The present disclosure relates to fire extinguisher systems and theircomponents. According to various embodiments, a fire extinguisher systemcomprising a broadhead cutter configured to pierce a burst disc, abroadhead cutter shaft coupled to the broadhead cutter, a spring systemcoupled to a broadhead cutter shaft, and a spring releasing mechanismcoupled to the spring system are described herein. The spring releasingmechanism may be electrically activated. A collect may be configured toretain the spring system in a non-actuated position. A pull rod may beconfigured to retain the collect in a standby position. A stop ring maybe configured to retain the broadhead cutter shaft within a dischargehead. The broadhead cutter is configured to pierce the burst disc inresponse to actuation of the spring system. The fire extinguisher systemmay be pyrotechnic free. The burst disc may be configured to petal outin response to piercing by the broadhead cutter. The pressure andextinguishing agent being expelled from within the fire extinguisher mayaid in opening of petals of the burst disc.

According to various embodiments, a method of actuating an extinguishersystem is described herein. The method may include retaining a broadheadcutter in close proximity to a burst disc surface. The method mayinclude receiving an impulse signal. The method may include actuating aspring release mechanism in response to receiving the impulse signal.The method may include driving a cutter shaft towards the burst discsurface in response to actuation. The method may include piercing theburst disc via a broadhead cutter coupled to the cutter shaft. A collectmay be configured to retain the spring release mechanism in a standbyposition. The spring release mechanism may be actuated by an electricalactuation signal. Travel of the cutter shaft may be stopped via physicalcontact with a stop ring. The pressure and extinguishing agent beingexpelled from within the fire extinguisher aid in opening of petals ofthe burst disc. The burst disc is configured to petal out in response topiercing by the broadhead cutter.

BRIEF DESCRIPTION OF THE DRAWINGS

The subject matter of the present disclosure is particularly pointed outand distinctly claimed in the concluding portion of the specification. Amore complete understanding of the present disclosure, however, may bestbe obtained by referring to the detailed description and claims whenconsidered in connection with the drawing figures, wherein like numeralsdenote like elements.

FIG. 1 depicts a prior art fire extinguisher system;

FIG. 2 depicts an advanced fire extinguisher system in accordance withvarious embodiments;

FIG. 3 depicts an advanced fire extinguisher system and its componentsin accordance with various embodiments;

FIGS. 4A, 4B and 4C depict a fire extinguisher which is activated uponcommand by releasing the elastic potential energy of a spring system todrive a broadhead cutter configured to rupture a hermetic burst disc inaccordance with various embodiments;

FIGS. 5A and 5B depict a whole burst disc and a pierced burst disc,respectively, in accordance with various embodiments;

FIG. 6 depicts a broadhead burst disc cutter, in accordance with variousembodiments; and

FIG. 7 depicts a method of actuating an advanced fire extinguishersystem, in accordance with various embodiments.

DETAILED DESCRIPTION

The detailed description of exemplary embodiments herein makes referenceto the accompanying drawings, which show exemplary embodiments by way ofillustration and their best mode. While these exemplary embodiments aredescribed in sufficient detail to enable those skilled in the art topractice the disclosure, it should be understood that other embodimentsmay be realized and that logical changes may be made without departingfrom the spirit and scope of the disclosure. Thus, the detaileddescription herein is presented for purposes of illustration only andnot of limitation. For example, the steps recited in any of the methodor process descriptions may be executed in any order and are notnecessarily limited to the order presented. Furthermore, any referenceto singular includes plural embodiments, and any reference to more thanone component or step may include a singular embodiment or step.

The present disclosure relates to fire extinguisher systems and theircomponents. According to various embodiments and with reference to FIG.2, a burst disc assembly 210 is ruptured from inside the fireextinguisher. In contrast to traditional systems, the explosivecartridge is replaced by a broadhead cutter 260 attached to an actuator.The actuator may be any desired actuator. For instance, the actuator maybe a cutter shaft 250 which will be put in motion by the release of theelastic potential energy of a spring system 220. A discharge head 320(with brief reference to FIG. 3) may be used for interfacing to theaircraft plumbing/tubing to direct the agent to the desired location. Adebris screen is not utilized in the discharge head 320 because thebroadhead cutter 260 does not produce fragments when the fireextinguisher outlet burst disc assembly 210 is ruptured.

FIG. 2 illustrates a broadhead cutter 260 activation mechanism andsystem 200 inside of a fire extinguisher in accordance with variousembodiments. Fire extinguisher system 200 may be pyrotechnic free. Thefire extinguisher may comprise an internal volume area 230. Fireextinguishers can range in size 40 cubic inches to 2500+ cubic inches.The fire extinguisher may comprise a burst disc assembly 210. The burstdisc assembly 210 may be made from any suitable material configured tobe pierced by the broadhead cutter 260. The broadhead cutter 260 devicemay be attached to a cutter shaft 250 which is driven downward (towardsthe center of the burst disc assembly 210) in response to the elasticpotential energy being released from the spring system 220. The springsystem 220 releasing mechanism 240 may be, for example, a solenoid, amotor, such as a DC motor, a DC geared motor, a linear motor, arotational solenoid using a ratcheted drive mechanism, and/or the like.

It should be noted that any structure located inside of the fireextinguisher associated with the support/stabilization of the mechanismsdescribed below, as well as the routing of the electrical connectionsfrom the electrical connector 310, with brief reference to FIG. 3, tothe spring system 220 releasing mechanism 240 are not shown in order tosimplify the drawings.

According to various embodiments and with reference to FIG. 3, a pullrod 350 (aka a lock pin) is used to hold the collet 340 in a closed(forced outward) position to keep the spring system 220 compressed. Thecollet 340 is pushed outward so its outer flange 342 engages a recess252 within the cutter shaft 250, so it is retained and cannot be moveddownward (towards the discharge head 320 by the compressed spring system220. Therefore, the spring system 220 is held in a compressed state by aportion of the cutter shaft 250. The spring system 220 can be any typeof a spring system, such as Bellville washers, helical/coil spring,and/or the like.

According to various embodiments and with continued reference to FIG. 3,a lock pin spring 370 may be used to apply a positive pressure on thepull rod 350 so the pull rod 350 maintains the collet 340 in a closed(force outward) position. The lock pin spring 370 is utilized so thepull rod 350 is retained in its normal position during periods of shockand vibration.

According to various embodiments and with reference to FIG. 4A, in astandby mode, the spring system 220 is held in compression by a face 255of the cutter shaft 250. In the standby mode the broadhead cutter 260 isin a first position 410 in proximity to but not in contact with theburst disc assembly 210. The outer flange of the collet 340 retains thecutter shaft 250 in a retaining position 460. The pull rod 350 may be ina normal position 490 in standby mode holding the collet 340 in a forcedoutward position. Should the extinguisher be activated, an electricalimpulse may be sent via an electrical connection 380 to the springsystem release mechanism 240 (as depicted in FIG. 2 and FIG. 3). Springsystem release mechanism 240 pulls the pull rod 350 upward from itsnormal position in standby mode holding the collet 340 in a forcedoutward position.

According to various embodiments and with reference to FIG. 4B, inresponse to the pull rod 350 being pulled upward, as described above, anouter flange of the collet 340 is no longer being held in place againstthe recess in the cutter shaft 250, so the force of the spring system220 on the cutter shaft 250 is now free and/or available to push thecutter shaft 250 downward as the collet 340 fingers flex radially inwardwith respect to collet 340. The spring system may be in a flex position465. As the cutter shaft 250 moves downward to a downward position 480,the broadhead cutter 260 pierces the burst disc assembly 210. In thisway, the broadhead cutter 260 is in a piercing position 420. Thedownward movement of the cutter shaft 250 and/or broadhead cutter 260 isstopped by the stop ring 330.

According to various embodiments and with reference to FIG. 4C, inresponse to the broadhead cutter 260 penetrating the burst disc assembly210, the pressure and extinguishing agent being expelled from within thefire extinguisher aid in the opening of the petals of the burst discassembly 210 started by the broadhead cutter 260. Stated another way theburst disc assembly 210 may petal out and split into a plurality ofpetal like shapes, such as four petals, when pierced by the broadheadcutter 260. Moreover, the spring system 220 is in substantially fullyactivated and/or extended position 470. In this way, broadhead cutter260 is in a second position 430 where the burst disc assembly 210 is atleast substantially opened by the pressure and extinguishing agentwithin the fire extinguisher. FIG. 4C also illustrates that that thecutter shaft 250 in its fully extended downward position 480 has beenstopped and retained by the stop ring 330 to keep the broadhead cutter260 from becoming a projectile. The broadhead cutter 260 starts theformation of the four petals, and the high pressure within the fireextinguisher completes the opening of the four petals to a substantiallyfully open position. The number of petals is related to the shape anddesign of the broadhead cutter 260.

According to various embodiments and with reference to FIG. 5A, anon-pierced burst disc assembly 210 is illustrated. According to variousembodiments and with reference to FIG. 5B, a pierced and substantiallyopened burst disc assembly 210 is illustrated. According to variousembodiments and with reference to FIG. 6, a single pronged broadheadcutter 260 is depicted. The broadhead cutter 260 may take any formfactor. The broadhead cutter 260 is configured for piercing the burstdisc assembly 210.

According to various embodiments and with reference to FIG. 7, a methodof actuating an extinguisher system is illustrated using a flow chart.The method may include retaining a broadhead cutter in close proximityto a burst disc surface (Step 710). The method may include receiving animpulse signal (Step 720). The method may include actuating a springrelease mechanism in response to receiving the impulse signal (Step730). The method may include driving a cutter shaft towards the burstdisc surface in response to actuation (Step 740). The method may includepiercing the burst disc via a broadhead cutter coupled to the cuttershaft (Step 750). A collet 340 may be configured to retain the springrelease mechanism in a standby position. The spring release mechanismmay be actuated by an electrical actuation signal. Travel of the cuttershaft 250 may be stopped via physical contact with a stop ring. Thepressure and extinguishing agent being expelled from within the fireextinguisher aid in opening of petals of the burst disc assembly 210(Step 760). The burst disc assembly 210 is configured to petal out inresponse to being pierced by the broadhead cutter 260 (Step 770).

Benefits, other advantages, and solutions to problems have beendescribed herein with regard to specific embodiments. Furthermore, theconnecting lines shown in the various figures contained herein areintended to represent exemplary functional relationships and/or physicalcouplings between the various elements. It should be noted that manyalternative or additional functional relationships or physicalconnections may be present in a practical system. However, the benefits,advantages, solutions to problems, and any elements that may cause anybenefit, advantage, or solution to occur or become more pronounced arenot to be construed as critical, required, or essential features orelements of the disclosure. The scope of the disclosure is accordinglyto be limited by nothing other than the appended claims, in whichreference to an element in the singular is not intended to mean “one andonly one” unless explicitly so stated, but rather “one or more.”

Systems, methods and apparatus are provided herein. In the detaileddescription herein, references to “various embodiments”, “oneembodiment”, “an embodiment”, “an example embodiment”, etc., indicatethat the embodiment described may include a particular feature,structure, or characteristic, but every embodiment may not necessarilyinclude the particular feature, structure, or characteristic. Moreover,such phrases are not necessarily referring to the same embodiment.Further, when a particular feature, structure, or characteristic isdescribed in connection with an embodiment, it is submitted that it iswithin the knowledge of one skilled in the art to affect such feature,structure, or characteristic in connection with other embodimentswhether or not explicitly described. After reading the description, itwill be apparent to one skilled in the relevant art(s) how to implementthe disclosure in alternative embodiments. Different cross-hatching isused throughout the figures to denote different parts but notnecessarily to denote the same or different materials.

Furthermore, no element, component, or method step in the presentdisclosure is intended to be dedicated to the public regardless ofwhether the element, component, or method step is explicitly recited inthe claims. No claim element herein is to be construed under theprovisions of 35 U.S.C. 112(f), unless the element is expressly recitedusing the phrase “means for.” As used herein, the terms “comprises”,“comprising”, or any other variation thereof, are intended to cover anon-exclusive inclusion, such that a process, method, article, orapparatus that comprises a list of elements does not include only thoseelements but may include other elements not expressly listed or inherentto such process, method, article, or apparatus.

What is claimed is:
 1. A method of actuating an extinguisher systemcomprising: retaining a broadhead cutter adjacent a burst disc surface;retaining a collet in a standby position via a pull rod, the colletencompassing the pull rod, the pull rod defines a centerline axis;retaining a spring system in a non-actuated position via the collet,wherein an outer flange of the collet is moved outward from thecenterline axis to engage a recess within a cutter shaft in response tothe spring system being retained in the non-actuated position; receivingan impulse signal; actuating a spring release mechanism in response toreceiving the impulse signal, wherein the spring releasing mechanismcomprises either a solenoid or a motor, the spring releasing mechanismcoupled to the spring system via the pull rod; moving the pull rod withrespect to the collet in response to the spring release mechanismactuating, moving the outer flange of the collet inward toward thecenterline axis to disengage the recess within the cutter shaft inresponse to the pull rod moving, driving the cutter shaft towards theburst disc surface, via the spring system, in response to the outerflange of the collet moving inward; and piercing the burst disc surfacevia the broadhead cutter coupled to the cutter shaft.
 2. The method ofactuating an extinguisher system of claim 1, wherein the cutter shaft isdriven by the spring system.
 3. The method of actuating an extinguishersystem of claim 1, further comprising stopping travel of the cuttershaft via physical contact with a stop ring.
 4. The method of actuatingan extinguisher system of claim 1, further comprising expellingextinguishing agent from within a fire extinguisher to aid in opening ofthe burst disc surface.
 5. The method of actuating an extinguishersystem of claim 1, wherein the burst disc surface is configured to petalout in response to piercing by the broadhead cutter.